Negative-saliency PMSM in which L_d is higher than L_q can achieve wider speed range, therefore it has a broad application prospect in electric vehicles. The parameters vary greatly under different operation conditions, leading to deteriorate the performance of the controller. In this paper, an adaptive control method based on online parameter identification is proposed. In constant torque region, adaptive maximum torque per ampere control is realized based on online parameter identification. In constant power region, adaptive field weakening control based on a PI regulator is used. Simulation and experiment results verify the reasonableness and correctness of the proposed control strategies.